There are optical disks for recording information such as computer data, e.g., PDs. PD is a rewritable optical disk which employs the phase change system and performs recording and reproduction of data by sectors.
A problem associated with rewritable optical disks is that data recording and reproduction cannot be ensured for every sector due to dust attached to the disk, a scratch on the disk, deterioration of the disk material itself from repeated recording operations, or the like. Such a sector, from which data cannot be normally recorded/reproduced, is called a defective sector. Such a defective sector is typically replacement-recorded based on a linear replacement algorithm.
The linear replacement algorithm is a system where a large number of spare areas are provided in a particular area on the disk so as to replacement-record data to an appropriate sector in the spare area when a defective sector is detected, thereby ensuring the reliability of input data.
In recent years, AV processing environments have been improved in personal computer apparatuses, and it is becoming more common to enjoy audio/video titles with a personal computer apparatus using a CD-ROM, or the like, in which AV data is recorded as being compressed based on a system such as the MPEG system.
However, since the conventional rewritable optical disk and the disk drive apparatus therefor are designed while assuming the use for recording/reproducing computer data, there are various problems when recording/reproducing AV data having different characteristics from those of computer data.
Typically, there is a problem that continuous video reproduction cannot be ensured when reproducing AV data. This is because a defective sector detected during the recording of the AV data is replacement-recorded using a conventional defect management method, whereby the continuous reproduction of AV data is hampered by a delay associated with an access to the spare area during data reproduction.
This problem is particularly conspicuous in the case of the above-described linear replacement algorithm. For example, when a defective sector occurs in the innermost area of the disk while the spare area is provided in the outermost area of the disk, the head moves from the inner area of the disk to the outer area of the disk in accessing the spare area, thereby resulting in a seek time of several hundred milliseconds. Since picture reproduction of video at 30 frames per second is required, if such a seek time as long as several hundred milliseconds is generated, the reproduced images will consequently be interrupted.
A problem in AV data recording is that it is necessary to provide a variety of recording methods. For example, AV data to be transmitted in real time via a broadcast wave, or the like, has to be recorded on the disk in real time. On the other hand, when high quality AV data to be downloaded via the internet, or the like, is asynchronously recorded on the disk, the real time recording is not necessary, but data recording with high reliability is required.
The present invention has been made in view of the above problems and has an objective of providing method and apparatus for recording data which enable real time recording of AV data to a rewritable optical disk and continuous reproduction of the recorded AV data, a reproduction method, a reproduction apparatus and an information recording disk therefor, and an information processing system composed thereof.